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Brain interstitial fluid TNF-alpha after subarachnoid hemorrhage.
Khalid A Hanafy1, Bartosz Grobelny, Luis Fernandez
1Division of Critical Care Neurology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA. kh2401@columbia.edu
Journal of the Neurological Sciences
|January 30, 2010
Summary
Tumor necrosis factor-alpha (TNF-alpha) levels increase after subarachnoid hemorrhage (SAH). Elevated brain interstitial TNF-alpha is linked to larger aneurysm size, intraventricular hemorrhage, and higher brain glucose levels.
Area of Science:
- Neuroscience
- Inflammation Biology
- Critical Care Medicine
Background:
- Tumor necrosis factor-alpha (TNF-alpha) is a key inflammatory cytokine.
- Emerging evidence suggests TNF-alpha's role in cerebral aneurysm formation and rupture.
- Cerebral inflammation significantly impacts outcomes following subarachnoid hemorrhage (SAH).
Purpose of the Study:
- To investigate the association between brain interstitial fluid TNF-alpha levels and clinical parameters in comatose SAH patients.
- To identify predictors of elevated TNF-alpha in the brain interstitial fluid following SAH.
Main Methods:
- Studied 14 comatose SAH patients undergoing multimodal neuromonitoring.
- Utilized intracranial pressure (ICP) and cerebral microdialysis for continuous monitoring.
- Time-locked physiological variables with brain interstitial fluid TNF-alpha measurements; analyzed using generalized estimation equations.
Main Results:
- Mean of 9 TNF-alpha measurements per patient over ~72 hours of monitoring.
- Progressive increase in brain interstitial TNF-alpha levels over time.
- Predictors of elevated TNF-alpha included higher brain interstitial glucose, intraventricular hemorrhage, and aneurysm size >6mm.
Conclusions:
- Brain interstitial TNF-alpha levels are elevated post-SAH.
- Elevated TNF-alpha is associated with larger aneurysm size, intraventricular hemorrhage burden, and increased brain interstitial glucose.
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